It is known to provide display devices, such as computer screens, with a touch-sensitive input area in order to move or control a cursor on the display area, for instance, by means of a finger by moving the finger. However, this concept of operation has the disadvantage that a user must take his hand off the keyboard in order to move the cursor on the display area of the screen. Thus, this concept of operation does not substantially differ from a corresponding input of the user via a separate computer mouse. It has been tried to overcome this disadvantage by providing respective input devices for controlling or moving a cursor already on the keyboard.
For example, keyboards are known, comprising a so-called track point in the area of the numeric pad or in the area of the alpha-numeric pad of the keyboard, which can be moved with a finger of a hand resting on the keyboard. However, moving such a trackpoint demands great skill and is furthermore hard to learn so that a user finally reverts to an external mouse despite an existing track point. Since a trackpoint is arranged between the keys of a keyboard, it can, on the one hand, interfere with the intended use of the keyboard, namely the input of text, and, on the other hand, an unintended moving of the track point cannot be avoided when entering text.
Another approach to solving the problem is to arrange a so-called trackball on or at the keyboard, which also enables the control of a computer mouse. Due to the size of the trackball said trackball is arranged outside the pad, which, however, has the disadvantage that a user has to take his hand off the pad and move it to the trackball for controlling the cursor. Another disadvantage is that a trackball requires additional space on the keyboard so that the entire keyboard tends to be larger in size.
Another known approach to solve the problem is to provide an additional entry field on the keyboard, for example next to the numeric pad, which is configured as touch-sensitive entry field. Moving a finger on the touch-sensitive entry field can cause a cursor to move on the screen. This concept also has the disadvantage that a user has to take his hand off the keypad in order to perform an input on the touch-sensitive area of the keyboard. Moreover, additional space is required for the touch-sensitive entry field, resulting in larger keyboards.